// Thud - a dynamic object-oriented language
// Copyright (C) 2009,2010 David H. Hovemeyer <david.hovemeyer@gmail.com>

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

/*
 * InputStream.cpp
 *
 *  Created on: Dec 14, 2009
 *      Author: dhovemey
 */

#include <cassert>
#include "util/Error.h"
#include "util/EOFException.h"
#include "util/InputStream.h"

InputStream::InputStream()
{

}

InputStream::~InputStream()
{

}

size_t InputStream::readFully(void *buf_, size_t n)
{
	size_t off = 0;
	char *buf = (char *) buf_;

	while (off < n) {
		size_t left = n - off;
		size_t rc = read(buf + off, left);

		if (rc == 0) {
			if (atEOF()) {
				// EOF was reached before all bytes could be read
				Error::raise(new EOFException(n));
			}
#ifndef NDEBUG
			else {
				// This should only happen if an I/O error occurred
				assert(error());
			}
#endif
			return off;
		}

		off += rc;
	}
	assert(off == n);
	return n;
}

